It won't turn on. it showed a "locking" screen and now it doesn't work.

[142-L1M]

Hi, i'm sorta new to this stuff, but i kinda need help. Last night my brother and i were playing Roblox, when suddenly his screen turned black, and displayed a "locking" screen before completely shutting off. Now it won't turn on, no matter what we do to try and fix it. if it helps anyone answer, he had switched out of S mode beforehand, like a week after he got his laptop.

[Echo_Lake]

@142-L1M

Thank you for posting on the HP Support Community.
 

Don't worry as I'll be glad to help, 

I appreciate your efforts to try and resolve the issue. If you have already performed the steps from the document HP Notebook PCs - Computer Does Not Start: https://support.hp.com/in-en/document/c01997899, No Power or no Boot and the issue persists, it could be a hardware failure. 
 

I'm sending out a private message to assist you with the next course of action. Please check your Private message icon on the upper right corner of your HP Community profile Next, to your profile Name, you should see a little blue envelope, please click on it or simply click on this link: https://h30434.www3.hp.com/t5/notes/privatenotespage
 

Hope this helps! Keep me posted for further assistance.
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